The growth in laptop computers and handheld computing devices (e.g., PDAs (Personal Digital Assistant) has increased the need for users to seek network connectivity in many different locales. Wireless networks have thus gained popularity because of their convenience. However, security in a wireless networking environment is a serious concern. Because network traffic is broadcast over radio frequencies it becomes very easy for anyone with a proper radio receiver to intercept this traffic for the purpose of gaining vital information or for masquerading as a legitimate user. Protecting these communications is a strong requirement in mobile computing.
For wireless LAN (Local Area Network) communications, the 802.11 standard specifies the Wired Equivalent Privacy (WEP) in order to address the security issues, primarily protecting data confidentiality, inherent in this technology. The WEP protocol is an international standard and widely deployed. Unfortunately, it has been shown that WEP fails to achieve its data confidentiality goals leaving users vulnerable to a number of different attacks.
These vulnerabilities are well known and documented in, for example, J. R. Walker, “Unsafe at any key size: An analysis of the WEP encapsulations, IEEE document 802.11-00/362, 2001.” and references therein.
These security problems are a significant issue with regard to the use of the WEP. Further, combining the third generation wireless data access protocol General Packet Radio Service (GPRS)/Universal Mobile Telecommunications System (UMTS) to allow secure roaming between these networks is advantageous. Indeed, roaming between GPRS/UMTS networks across networks deemed insecure is a significant problem requiring a solution.